Building automation systems can be complex distributed systems. For example, a building automation system can include many different pieces of equipment. As a specific example, a building automation system can include different pieces of heating, ventilation, and air-conditioning (HVAC) equipment as well as other equipment such as sensors, operating panels, controllers, actuators, etc.
Detecting faults within a building automation system to maintain functionality of the building automation system can be important to provide a comfortable environment for occupants of an area (e.g., a room or a zone) of a building serviced by the building automation system, to prevent the building automation from further damage resulting from a detected fault, and/or to avoid inefficient operation of the building automation system which may result in higher energy consumption. For example, occupant comfort in a building serviced by a building automation system can be a direct result of the functionality of the building automation system, and occupant comfort may be quickly lost in the event a component of the building automation system, such as the equipment, fails.
Fault detection and diagnosis can help quickly determine faults of equipment and/or faults in control strategies in a building by using available system variables of a building automation system. System variables of a building automation system can include data from various types of physical sensors, data from control sequences, and/or data from other system variables (e.g., signals from controllers, actuators, and/or meters, etc.) For example, fault detection and diagnosis can help a user of the building automation system, such as an engineer, building manager, or other service personnel, and/or a system (e.g., a building automation system) to quickly detect faults, gain understanding of a current state of building operation, and/or schedule repairs of faults in a building automation system.